Debt and Demand

One interesting issue in the ongoing secular stagnation debate is the relationship between debt and aggregate demand. In particular, there’s been a revival of the claim that there is something like a one to one relationship between changes in the ratio of debt to income, and final demand for goods and services.

I would like to reframe this claim a bit, drawing on my recent work with Arjun Jayadev. [1] In a nutshell: Changes in debt-income ratios reflect a number of macroeconomic variables, and until you have a specific story about which of those variables is driving the debt-income ratio, you can’t say what relationship to expect between that ratio and demand. We show in our paper that the entire post-1980 rise in household debt ratios can be explained, in an accounting sense, by higher real interest rates. Conversely, if the interest rates faced by households are lower in the future, debt-income ratios will decline without any fall in demand for real goods and services.

You might not know it from the current discussion, but there is an existing literature on these questions. The relationship between leverage — especially household debt — and aggregate demand was explored in a number of papers around the time of the last US credit crisis, in the late 1980s. Perhaps I’ll write a proper review of this material at some point; a short list would include Benjamin Friedman (1984 and 1986), Caskey and Fazzari (1991), Alfred Eichner (1991) and Tom Palley (1994 and 1997). It’s unfortunate that these earlier papers don’t get referred to in today’s discussion of debt and demand, by either mainstream or heterodox writers. [2]

For most of these writers, the important point was that the effect of debt on demand is two-faced: new borrowing can finance additional expenditure on real goods and services, but on the other hand debt service payments (in the presence of credit constraints) subtract from the funds available for current expenditure. Eichner, for instance, uses the equation E = F + delta-D – DS, or aggregate expenditure equals cashflow plus debt growth minus debt service payments.

More generally, to think systematically about the relationship between debt and household expenditure, we need to start from a consistent set of accounts. The first principle of financial accounting is that, for any economic unit, total sources of funds must equal total uses of funds. There are many ways of organizing accounts, at the level of the individual household or firm, at the level of the sector, or at the level of the nation, but this equality must always hold. You can slice up sources and uses of funds however you like, but total money coming in must equal total money going out.

The standard financial accounts for the United States are the Flow of Funds, maintained by the Federal Reserve. A number of alternative accounting frameworks are reflected in the social accounting matrixes developed by the late Wynne Godley and Lance Taylor and their students and collaborators.

Here’s one natural way of organizing sources and uses of funds for the household sector:

compensation of employees
+
capital income
+
transfer receipts
+
net borrowing 
=
consumption (including consumer durables)
+
residential investment
tax payments
+
interest payments
net acquisition of financial assets

The items before the equal sign are sources of funds; the items after are uses. [3] The first two uses of funds are included in GDP measured as income, while the latter two are not. Similarly, the first two uses of funds are included in GDP measured as expenditure, while the latter three are not.

When we look at the whole balance sheet, it is clear that borrowing cannot change in isolation. An increase in one source of funds must be accompanied by some mix of increase in some use(s) of funds, and decrease in other sources of funds. So if we want to talk about the relationship between borrowing and GDP, we need a story about what other items on the balance sheet are changing along with it. One possible story is that changes in borrowing are normally matched by changes in consumption, or in residential investment. This is the implicit story behind the suggestion that lower household borrowing will reduce final demand dollar for dollar. But there is no reason in principle why that has to be the main margin that household borrowing adjusts on, and as we’ll see, historically it often has not been.

So far we have been talking about the absolute levels of borrowing and other flows. But in general, we are not interested in the absolute level of borrowing, but on the ratio of debt to income. It’s common to speak about changes in borrowing and changes in debt-income ratios as if they were synonyms. [4]  But they are not. The debt-income ratio has a denominator as well as a numerator. The denominator is nominal income, so the evolution of the ratio depends  not only on household borrowing, but on real income growth and inflation. Faster growth of nominal income — whether due to real income growth or inflation — reduces the debt-income ratio, just as much as lower borrowing does.

In short: For changes in the debt-income ratio to be reflected one for one in aggregate demand, two things must be true. First, changes in the ratio must be due mainly to variation in the numerator, rather than the denominator. And second, changes in the numerator must be due mainly to variation in consumption and residential investment, rather than variation in other balance sheet items. How true are these things with respect to the rise in debt-income ratios over the past 30 years?

To frame the question in a tractable way, we need to simplify the balance sheet, combining some items to focus on the ones we care about. In our paper, Arjun and I were interested in debt ratios, not aggregate demand, so we grouped together all the non-credit flows into a single variable, which we called the household primary deficit. We defined this as all uses of funds except interest payments, minus all sources of funds except borrowing.

Here, I do things slightly differently. I divide changes in debt into those due to nominal income growth, those due to expenditures that contribute to aggregate demand (consumption and residential investment), and those due to non-demand expenditure (interest payments and net acquisition of financial assets.) For 1985 and later years, I also include the change in debt-income ratios attributable to default. (We were unable to find good data on household level defaults for earlier years, but there is good reason to think that household defaults did not occur at a macroeconomically significant level between the Depression and the Great Recession.) This lets us answer the question directly: historically, how closely have changes in household debt-income ratios been linked to changes in aggregate demand?

Figure 1 shows the trajectory of household debt for the US since 1929, along with federal debt and non financial business debt. (All are given as fractions of GDP.) As we can see, there have been three distinct episodes of rising household debt ratios since World War II: one in the decade or so immediately following the war, one in the mid-1980s, and one in the first half of the 2000s.

Figure 1: US debt-GDP ratios, 1929-2011

Figure 2 shows the annual change in the debt ratio, along with the decomposition described above. All variables are expressed as deviations from the 1950-2010 average. The heavy black line is the change in the debt-income ratio. The solid red line is final-demand expenditure, i.e. non-interest consumption plus residential investment. The dashed and dotted blue lines show the contributions of nominal income growth and non-demand expenditure, respectively. And the purple line with diamonds shows the contribution of defaults. (Defaults are measured relative to the 1985-2010 average.)

Figure 2: Decomposition of changes in the household debt-income ratio, 1949-2011

It’s clear from this figure that there is an important element of truth to the Keen-Krugman view that there is a tight link between the debt-incoem ratio and demand. There is evidently a close relationship between household demand and changes in the debt ratio, especially with respect to short-term variation. But that view is also missing something important. In some periods, there are substantial divergences between final demand from household and changes in the debt ratio. In particular, the increase in the household debt ratio in the 1980s (by about 20 points of GDP) took place during a period when consumption and residential investment by households were near their lowest levels since World War II. The increase in household debt after 1980 has often been described as some kind of “consumption binge”; this is the opposite of the truth.

The ambiguous relationship between household debt and aggregate demand can be seen in Table 1, which compares the periods of rising household debt with the intervening periods of stable or falling debt. The numbers are annual averages; to facilitate comparisons between periods, the averages for sub periods are again expressed as deviations from the 1950-2010 mean. (Or from the 1985-2010 mean, in the case of defaults.) The numbers are the contributions to the change i the debt-income ratio, so a positive value for nominal income growth indicates lower inflation and/or growth than the postwar average.

Table 1: Decomposition of changes in the household debt-income ratio, selected periods

Change in debt-income ratio Contribution of nominal income growth Aggregate-demand expenditure Non-demand   expenditure Defaults
1950-2010 mean 1.5 -4.9 89.1 17.7 -0.9
Difference from mean:
1949-1963 1.3 2.3 2.9 -4.3 N/A
1964-1983 -1.6 -1.4 -1.8 1.1 N/A
1984-1989 1.4 -0.3 -2.1 3.8 0.4
1990-1998 -0.5 0.3 -0.8 0.3 0.2
1999-2006 3.2 -1.2 3.1 1.7 0.1
2007-2010 -3.5 1.7 -1.4 -2.0 -1.3

What we see here is that while the first and third episodes of rising debt are indeed associated with higher than average household expenditure on real goods and services, the 1980s episode is not. The rise in debt in the 1980s is explained by a rise in non-demand expenditures. Specifically, it is entirely due to the rise in interest payments, which doubled from 3-4 percent of household income in the 1950s and 1960s to over 8 percent in the late 1980s. (Interest payments continued around this level up to the Great Recession, falling somewhat only in the past few years. The reason “non-demand expenditures” is lower after 1990 is because the household sector sharply reduced net acquisition of financial assets.) Also, note that while the housing booms of 1949-1963 and 1999-2006 saw almost identical levels of household expenditure on real goods and services, the household debt ratio rose nearly twice as fast in the more recent episode. The reason, again, is because of much higher interest payments in the 2000s compared with the immediate postwar period. Finally, as I’ve pointed out on this blog before, the deleveraging since 2008 would have been impossible without elevated household defaults, which approached 4 percent of outstanding household debt in 2009-2010 — partly offset by the sharp fall in household income in 2009, which raised the debt-income ratio.

Figure 3, from our paper, offers another way of looking at this. The heavy black line is the actual trajectory of the household debt-income ratio. The other lines show counterfactual scenarios in which non-interest household expenditures are at their historical levels, but growth, inflation and/or interest rates are held constant at their 1946-1980 average levels.

Figure 3: Counterfactual scenarios for the evolution of household-debt income ratios, 1946-2010

All these counterfactual scenarios show a spike in the 2000s: People really did borrow to pay for new houses! But the counterfactual scenarios also show lower overall trends of household debt, indicating that slower income growth, lower inflation and higher interest rates all contributed to the rise of household debt post-1980, independent of changes in borrowing behavior. Most interestingly, the red line shows that new borrowing after 1980 was lower than new borrowing in the 1950s, 60s and 70s; if households had engaged in the exact same spending on consumption, residential investment and financial assets as they actually did, but inflation, growth and interest rates had remained at their pre-1980 levels, the household debt-income ratio would have trended gradually downward.

To the extent that rising debt-income ratios after 1980 were the result of higher interest rates and disinflation, they were not contributing to aggregate demand. And if lower interest rates and and, perhaps, higher inflation and/or higher default rates bring down debt ratios in the future, deleveraging will not be a headwind for demand. 

It is customary to see rising debt as the result of private choices to finance higher expenditures by issuing new credit-market liabilities. But historically, it is equally correct to see rising debt as the result of political choices that increase the real value of existing liabilities.

[1] I’m pleased to report that a version of this paper has been accepted for publication by American Economic Journal: Macroeconomics. This has caused some adjustment in my view of the permeability of the “mainstream-heterodox” divide.

[2] This neglect of the earlier literature is especially puzzling since several of the protagonists of the 1990-era discussion are active in the sequel today. Steve Fazzari, for instance, in his several superb recent papers (with Barry Cynamon) on household debt, does not refer to his own 1991 paper, tho it is dealing with substantially the same questions. 

[3] Only a few minor items are left out. This grouping of sources and uses of funds essentially follows Lance Taylor’s social accounting matrices, as presented in Reconstructing Macroeconomics and elsewhere. Neither the NIPAs nor the Flow of Funds present household accounts in exactly this way. The Flow of Funds groups all three sources of household income together, treats consumer durables as a separate category of household investment, and treats interest payments as consumption. The NIPAs treat residential investment and mortgage interest payments as their own sector, separate from the household sector, and omits borrowing and net acquisition of financial assets. The NIPAs also include a number of noncash items, of which the most important is the imputed flow of housing services from the owner-occupied housing sector to the household sector and the corresponding imputed rental payments from the household sector to the owner-occupied residential sector.

[4] For example, a recent paper on the causes of “The Rise in U.S. Household Indebtedness” begins with the sentence, “During the past several decades in the United States, signi ficant changes have occurred in household saving and borrowing behavior,” with no sign of realizing that this is a different question than the one posed by the title.

What Is Business Borrowing For?

In comments, Woj asks,

have you done any research on the decline in bank lending for tangible capital/investment?

As a matter of fact, I have. Check this out:

Simple correlation between borrowing and fixed investment

What this shows is the correlation between new borrowing and fixed investment across firms, by year (Borrowing and investmnet are both expressed as a fraction of the firm’s total assets; the data is from Compustat.) So what we see is that in the 1960s and 70s, a firm that was borrowing heavily also tended to be investing a lot, and vice versa; but after 1985, that was much less true. The same shift is visible if we look at the relationship between investment and borrowing for a given firm, across years: There is a strong correlation before 1980, but a much weaker one afterward. This table shows the average correlation of fixed investment for a given firm across quarters, with borrowing and cashflow.

Average correlation of fixed investment for a given firm.

So again, pre-1980 a given firm tended to borrow heavily and invest heavily in the same periods; after 1980 not so much.

I think it’s natural to see this change in the relation between borrowing and investment as a sign of the breakdown of the old hierarchy of finance. In the era of the Chandler-Galbraith corporation, payouts to shareholders were a quasi-fixed cost, not so different from bond payments. The effective residual claimants of corporate earnings were managers who, sociologically, were identified with the firm and pursued survival and growth objectives rather than profit maximization. Under these conditions, internal funds were lower cost than external funds, as Minsky, writing in this epoch, emphasized. So firms only turned to external finance once lower-cost internal funds were exhausted, meaning that in general, only those firms with exceptionally high investment demand borrowed heavily; this explains the strong correlation between borrowing and investment.

from Hubbard, Fazzari and Petersen (1988)

But since the shareholder revolution of the 1980s, this no longer really holds; shareholders have been much more effective in making their status as residual claimants effective, meaning that the opportunity cost of investing out of internal funds is no longer much lower than investing out of external funds. It’s no longer much easier for managers to convince shareholders to let the firm keep more of its earnings, than to convince bankers to let it have a loan. So the question of how much a firm borrows is now largely independent of how much it invests. (Modigliani-Miller comes closer to being true in a neoliberal world.)

Fun fact: Regressing nonfinancial corporate borrowing on stock buybacks for the period 2005-2010 yields a coefficient not significantly different from 1.0, with an r-squared of 0.98. In other words, it seems that the marginal dollar borrowed by a nonfinancial business in this period was simply handed on to shareholders, without funding any productive expenditure at all. This close fit between corporate borrowing and share buybacks raises doubts about the contribution of the financial crisis to the downturn in the real economy.

The larger implication is that, with the loss of the low-cost pool of internal funds, the hurdle rate for investment by nonfinancial firms is higher than it was during the postwar decades. In my mind this — more than inequality, tho it is of course important in its own right — is the structural condition for the Great Recession and the previous jobless recoveries. The downward shift in investment demand means that aggregate demand falls short of full employment except when boosted by asset bubbles.

The end of the cost advantage of internal funds (and the corresponding erosion of the correlation between borrowing and investment) is related to the end of the collapse of the larger post-New Deal structure of financial repression that preferentially channeled savings to productive investment.

UPDATE: I should clarify that while share buybacks are very large quantitatively — equal to total new borrowing by nonfinancial corporations in recent years — they are undertaken by only a relatively small group of firms. For smaller businesses, businesses without access to the bond market and especially privately held businesses, there probably still is a substantial wedge between the perceived cost of internal and external funds. It is quite possible that for small businesses, disruptions in credit supply did have significant effects. But given the comparatively small fraction of the economy accounted for by these firms, it seems unlikely that this could be a major cause of the recession.

Bottom Rail, Moving Up

David Harvey observed recently that this crisis was the first in modern times in which the periphery has not borne a disproportionate share of the costs. Dani Rodrik’s recent posts make a similar point.

And it’s true — over the past 40 years, we’ve seen repeated episodes when growth has slowed in the rich world, and collapsed catastrophically in the South. Neoliberalism has meant the tools the North uses to ameliorate slumps have been forbidden to poor countries. As my friend Doug Henwood says, in each of the crises of the past two decades, “the First World banks got a Minsky bailout while the Third World suffered a Fisher deflation.” But this time really seems to be different.
It’s interesting to compare the last of those episodes, the Asian crisis of 1997, with the most recent crisis.
Whatever you think the underlying causes of the 1997 crisis were (people sure liked saying “crony capitalism”) the basic facts are straightforward. East and Southeast Asia experienced a “sudden stop” of previously large financial inflows, leaving them unable to meet their foreign-currency obligations. As a result they were forced to abandon their currency pegs, abruptly raise interest rates to unheard-of levels, and eliminate their trade deficits with extreme prejudice. The result was severe economic disruption and brutal recessions. Indonesia, for example, didn’t regain its pre-crisis level of output for a full five years.
Fast forward ten years, and the same region is a bright spot in the global growth picture. What people don’t realize, though, is that many Asian countries experienced a sudden stop of financial inflows in 2007-08 even larger than the one that caused so much destruction in 1997. Add to that a collapse in export earnings as demand in the rich countries fell, and Asian countries faced a substantially larger shock to foreign exchange earnings in 2007-2008 than ten years before.
Change in Gross Flows as Percent of Peak GDP
1997Q2-1997Q4 Peak-2008Q4
Portfolio Inflows All Forex Inflows Portfolio Inflows All Forex Inflows
Indonesia -10.6 -18.5 -6.1 -9.7
Korea -5.9 -18.0 -10.1 -29.5
Phillipines -5.4 -15.9 -9.3 -30.1
Thailand -2.5 -12.4 -6.2 -22.4
Source: IMF International Financial Statistics.
Notes: [1]
As the table shows, several of the newly industrializing countries of East Asia experienced a shock to their balance of payments in 2007-08 about double that of 1997. So why did the earlier shock have so much larger effects?
“Floating exchange rates” is the wrong answer. (“Fiscal responsibility” is worse, it’s not even wrong.) As captured in the well-known J-curve, even when exchange rates move in the right direction, they initially have the wrong effects on trade flows. Even in the most optimistic case it takes at least a year before a depreciation begins to improve the trade balance. Anyway, in the crisis this time, Asian exchange rates didn’t fall. 
In the short run at least, trade flows respond to movements in incomes, not relative prices. Replacing the trade-price relationship with a trade-income relationship is probably the key contribution of Post Keynesian analysis to the study of international finance and trade. [2] Combined with the notion of liquidity constraints — despite what the textbook says, the supply of credit is not infinitely elastic at “the” interest rate — this means there are situations where a country needs to rapidly improve its balance of payments and the only tool available (once direct import restrictions are ruled out) is to reduce income, often by some large multiple of the gap to be closed. [3] In a nutshell, that’s what happened in 1997. So why not this time?
The answer is that the Asian countries entered this crisis, unlike the last one, with large current account surpluses and foreign-exchange reserves. Countries that can respond to a negative shock to foreign exchange inflows by reducing their own accumulation of foreign assets or spending down their reserves, don’t have to reduce imports by pushing down income and output. Instead, they could and did raise domestic incomes via stimulus programs and interest-rate cuts, to offset the fall in export demand. And this is not only good news for them, it also dampens the process by which trade-induced contractions would otherwise propagate across borders.
Indeed, it’s probably precisely to be ready for this contingency that Asian countries committed themselves to running surpluses in the first place. There’s an old Martin Wolf column making this argument, which I’ll add to this post when/if I find it. It’s made more systematically in a couple recent articles by Jorg Bibow. (Bibow’s work is about the best I’ve seen on the whole question of “global imbalances”.) He argues that current account surpluses and reserve accumulation should be seen as a form of “self-insurance” by countries that have become disillusioned with the IMF as a provider of insurance against balance-of-payments shocks (its supposed raison d’etre). Bibow is fairly critical of this approach, which is natural from the point of view of someone steeped in Keynes’ ideas of a rational international order. We don’t, after all, think it would be such a great thing if people dispensed with health insurance and saved up money for future health expenses instead. But if your insurer insisted that you donate at least a kidney before they’d approve a blood transfusion, self-insurance might look like a better option.

There’s a couple important points here. First, the economic point:

The direct effects of trade flows on aggregate demand are usually dwarfed by the indirect effects, as government spending and investment adjust to accommodate the balance of payments constraint. This is why trade is not, in a Keynesian framework, a zero-sum game, and why the mewling of American economists about Asian “mercantilism” so misses the point. When capital flowed out of Asia in 1997, the whole development process had to be thrown into reverse in order to make up the shortfall in foreign exchange. That’s what happens when you’re pushed up against your balance of payments constraint. It didn’t haVppen this time because of their past ten years of self-insurance. In the US, on the other hand, the external balance doesn’t constrain expansionary fiscal policy at all, only the stupidity of our politics does.

Maybe even more important, the political point. How is it that these countries managed to reject the siren song of the Washington Consensus? After all, it promised (1) development would be so much faster with access to the savings of the rich world via unfettered financial flows; (2) if something did go wrong, the IMF loans were always available to bridge short-term foreign-exchange shortfalls; and, implicitly, (3) if things fell apart completely, unrestricted financial flows would ensure that elites could extract their wealth from a wrecked economy.

Around 1990, when I was first becoming aware of politics, we took it for granted that the IMF was one of the great forces for evil in the world. And you know what? I think we were right.

Which makes it all the more remarkable that some substantial fraction of the world has managed to tear itself free of those usurers. In principle, there’s the potential for progressive struggle whenever the sociological basis of a form of political consciousness requires it to cohere somewhere beneath the top of a value chain. But in practice, it’s hard to do. Much easier for the representatives of a subordinate class or geography to constitute themselves as an agent of the elites above rather than the masses below. So while self-insurance via reserve accumulation might seem like a small step towards socialism, I think it’s kind of a big deal. Economically, you have to recognize that Asian economies are not in depression now thanks to prudential state action, not the pseudo-logic of “conditional convergence”. And politically it’s even more remarkable, in the scale of things, that Asian elites have been able even to this extent to identify themselves with their national economies rather than the global owning class.

[1] “All Forex Inflows” is the sum of gross portfolio inflows, inward FDI, other inward investment and exports. (The gross numbers are conceptually the correct ones, for reasons I can’t explain here but hopefully are obvious.) The peak quarter is 1997Q2 for the 1997 crisis. For the recent crisis it is  2008Q2 for Indonesia, 2007Q4 for Korea, 2007Q2 for the Philippines and 2008Q1 for Thailand. The IMF does not have data for Malaysia prior to 1999.

[2] As on so many topics, Joan Robinson’s contribution is essential and mostly unacknowledged.

[3] The ratio of the necessary fall in output to the balance of payments gap to be closed is equal to one over the marginal propensity to import. Countries in this situation almost always sharply raise the domestic rate of interest, which theoretically helps attract short-term financial flows to bridge the gap, but in practice is mostly just a mechanism to reduce domestic incomes.

The Financial Crisis and the Recession: Two Datapoints for the Skeptics

One of the most dramatic features of the financial crisis, for those who were following it obsessively in the autumn of 2008, was the near-freezing up of the commercial paper market. Commercial paper is short-term debt sold in markets rather than advanced by banks. It’s mostly very short maturity — days, weeks or months, not years. It’s generally cheaper than other forms of financing, but firms that rely on it need to be able to borrow more or less continuously. Doubts about their financial condition, or even the suspicion that other lenders might have doubts, can quickly push them up against their survival constraint. This is what happened to a number of financial institutions — most spectacularly Lehman Brothers — in the third quarter of 2008. The breakdown in the commercial paper market was one of the things that convinced people the financial universe was imploding, and taking the real economy down with it.
The story, implicit or explicit, was that the suddenly reduced or uncertain value of financial assets, and the seizing-up of the interbank markets, left banks unable or unwilling to hold the liabilities of nonfinancial businesses, i.e., to lend. These businesses found themselves unable to finance new investment or even routine operations, leading to the Great Recession. This is essentially the same story that Milton Friedman told (and Peter Temin, among others, criticized), about the Great Depression, but it’s also more or less the consensus view of the 2008-09 crisis among New Keynesian economists. For example:
A large decrease in the value of asset holdings of financial institutions resulted in dramatic intensification of the agency problems in those institutions … Credit spreads widened and credit rationing became widespread. The diminished ability to finance the acquisition of capital goods resulted in huge cutbacks of all types of investment.

The same story was widespread in the business journalism world, with people like Andrew Ross Sorkin writing, “Commercial paper, the workaday stuff that lets companies make payroll, was suddenly viewed as radioactive — and business activity almost stopped in its tracks.” Most importantly, this was the view of the crisis that motivated — or at least justified — the choice of both the Bush and Obama administrations to make strengthening bank balance sheets their number one priority in the crisis. But is it right? There are reasons for doubt.

Data from FRED. 

See, here’s a funny thing. I haven’t seen it discussed anywhere, but it’s very interesting. The commercial paper of financial and nonfinancial firms, normally interchangeable, fared quite differently in the crisis. Up til then, both had tracked the federal funds rate closely, except in the early 90s (the last by-general-agreement credit crisis) when both had risen above it. But as the figure above shows, in the fall of 2008, right around the Lehmann failure (the arrow on the graph), an unprecedented gap opened up between the interest lenders demanded on commercial paper from financial versus nonfinancial companies.

The implication: The state of the interbank lending market isn’t necessarily informative about the availability of credit to nonfinancial firms. It’s perfectly possible that lots of big banks had made lots of stupid bets in the real estate market, and once this became known other banks were unwilling to lend to them. But they remained perfectly willing to lend to everyone else — perhaps even on more favorable terms, since those funds had to go somewhere. The divergence in commercial paper rates is hardly dispositive, of course, but it at least suggests that the acute phase of the financial crisis was more of a problem for the financial sector specifically than for the economy as a whole

Second. Sorkin calls commercial paper “the workaday stuff that lets companies meet payroll.” This kind of language was everywhere for a while — that the financial crisis threatened to stop the flow of short-term credit from banks, and that without that even the most routine business functions would be impossible.

One of the central political-economic facts of our time is that public discussion of the economy is entirely dominated by finance. The interests of banks differ from those of other businesses on many dimensions; one of them is banks’ dependence on short-term financing. Financial firms are defined by the combination of short-term liabilities and long-term assets; they need to borrow every day; that’s why they’re subject to runs. The fear of not being able to make payroll if you’re cut off, even briefly, from financial markets, is perfectly reasonable, if you’re a bank.
But if you’re not?
In fact, short-term debt is large relative to cashflow only for financial firms. Nonfinancial firms don’t finance operating expenses through debt, only investment. (And inventories and goods-in-progress, which are largely financed by credit from customers and suppliers, rather than from banks.) From Compustat:
Short-term debt as a fraction of total debt

Sector Median Mean
FIRE 0.56 0.55
Non-FIRE 0.16 0.23

Short-term debt as a fraction of cashflow
Sector Median Mean
FIRE 7.53 15.1
Non-FIRE 0.35 0.71

Short-term debt as a fraction of revenue
Sector Median Mean
FIRE 0.78 1.64
Non-FIRE 0.04 0.08

(FIRE is finance, insurance and real estate. Short-term here means maturities of less than a year. Cashflow is defined as profits plus depreciation.)
This isn’t a secret; but it’s striking how different are the financing structures of financial and nonfinancial firms, and how little that difference has penetrated into public debate or much of the economics profession. For the median financial firm, losing access to short-term finance would be equivalent to a 70 percent fall in revenues; few could survive. For the median nonfinancial firm, by contrast, loss of access to short-term finance would be equivalent to a fall in revenues of just 4 percent. Short-term finance is just not that important to nonfinancial firms.
So, the breakdown in short-term credit markets was largely limited to financial firms, and financial firms are anyway the only ones that really depend on short-term credit. I don’t claim these two pieces of evidence are in any way definitive — I’ve got a long paper on this question in the works, which, well, won’t be definitive either — but they are at least consistent with the story that the financial crisis, on the one hand, and the fall of employment and output, on the other, were more or less independent outcomes of the collapse of the housing bubble, and that the state of the banks was not the major problem for the real economy.

EDIT: For the life of me, I can’t get either graphs or tables to look good in Blogger.